<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title></title>
    <style>
        * {
            padding: 0;
            margin: 0;
            box-sizing: border-box;
        }
        html, body {
            width: 100%;
        height: 100%;
        background-color: aqua;
        }
        .head {
            border: 2px solid #ccc;
        display: flex;
        align-items: center;
        justify-content: center;
        height: 60px;
        background-color: orange;
        color: aliceblue;
        position: relative;
        font-size: 35px;
        }
        .user {
        width: 60px;
        height: 60px;
        border-radius: 50%;
        display: block;
        background-color: blueviolet;
        right: 10px;
        position: absolute;
        display: flex;
        align-items: center;
        justify-content: center;
        font-size: 20px
        }
        .User {
        height: 80px;
        width: 60px;
        display: none;
        background-color: blueviolet;
        bottom: 30px;
        position: absolute;
        top: 60px;
        right: 0px;
        font-size: 10px !important;

        }
        .user:hover .User {
            display: block;
        }
        .user p {
            margin: 0;
            padding: 5px;
            text-align: center;
            cursor: pointer;
            transition: background 0.3s;
        }
        .container {
            display: flex;
            height:100%;
        } 
        .emo1 {
            flex: 2;
            background-color: #c43939;
        }
        .emo1 ul {
            list-style: none;
            margin-left: 15px;
            flex: 20;
        }
        .emo2 {
            flex: 7;
            background-color: cyan;
        } 
    </style>
</head>
<body>
    <div class="head">学生管理系统
        <div class="user">四班
            <div class="User">
                <p>个人信息</p>
                <p>修改密码</p>
                <p>退出登录</p>
            </div>
        </div>
    </div>
    <div class="container">
        <div class="emo1">
            <ul>
                <li>个人中心
                    <ul>
                        <li>个人性息</li>
                        <li>班级信息
                            <li>代号</li>
                            <li>姓名</li>
                            <li>年龄</li>
                            <li>性别</li>
                        </li>
                    </ul>
                </li>
                <li>学校信息</li>
                <li>成绩信息
                    <ul>
                    <li>课程成绩</li>
                </ul>
                </li>
                <li>考勤信息</li>
            </ul>
        </div>
        <div class="emo2"></div>
    </div>
</body>
</html>
<script src="test-1.js"></script>
<script>
    $(function(){
        $("li:has(ul)").click(function(e){
            if(this == e.target){
                if($(this).children().is(":hidden")){
                    $(this).css("list-style-image", "url(minus.gif)")
                    .children().show();
                } else {
                    $(this).css("list-style-image", "url(plus.gif)")
                    .children().hide();
                }
            }
            return false;
        }).css("cursor", "pointer").click();
        $("li:not(:has(ul))").css({
            "cursor": "default",
            "list-style-image": "none"
        });
    });
</script>
